While I was replacing the air filter in my 87 F150 (5.8L Cabureted) I noticed that the air intake snorkel had a vacuum motor that was just basically sitting there doing nothing because the tab used to hold it firmly in place was broken. I realize that this is not a critical piece of equipment because it basically just controls whether the carb gets the heated air from the pre-heater hose or not (my manifold doesn't have the heat shield or preheater hose attached anyway), but the vacuum going to this device/motor seems very weak. Should I be concerned that the vacuum going to this motor is weak?

 

Do you have access to a vacuum gauge?
Numbers are more useful than "weak" or "strong"

 

That vacuum is thermostatically controlled - so it should vary.

 

I have a hand-held vacuum pump with a guage on it. Would that work? If I just attached the hose from the engine to the vacuum pump, should that pull a reading on the guage?